Metal tube.



No. 650,575. Patented May 29, I900. C. W. WHITNEY.

METAL TUBE.

PATENT or fice.

CHARLES w. WHITNEY, on NEW Your, N.

METAL TUBE.

SPECIFICATION forming part of Letters Patent filo. 650,5?5, dated May 29, 1909. Application filed August 31,1899. Serial No. 729,119. (No model.)

tubes for such boilers, that although corrugated will not be likely'to be choked by cinders, &c., passing into the tubes without being able to pass through, and thus forming the nucleus of a dam that will collect ashes and soot and finally close the tube, and nullify it as a steam-generator.

To these ends the invention consists of a steam-boiler having the tube-sheet at the furnace end provided with smaller perforations than the diameter of the body of the tubes and in fitting in said furnace-tube sheet tubes having their ends reduced, whereby the following advantages are attained:

First. By increasing the quantity and solidity of the water surrounding the end and keeping it cooler. As the result of this there would be less expansion and contraction, which I believe to be one of the prime causes of leaky tubes and which is, perhaps,the most serious annoyance the locomotive-engineer has to contend with. The vitality of the metal will also be much better preserved.

Second. By largely increasing the plain or unperforated surface of the tube-sheet, which 40 is by far the most valuable part of a fire tubular boiler for producing steam, owing to the direct impact or impingement of the gases upon it by the action of the draft.

Third. By strengthening and stiffening the 4 5 tube-sheet by reducing the size of the holes in it and by the increased spaces between the fire-box ends of the tubes, by which means they will be more firmly held and less liable to loosen and leak.

My invention, therefore, is designed not only to provide a tube in which the mouth is made smaller than the body for the purpose of preventing pieces of coal and cinder from passing into it too large to passthrough, but atube which develops many other advantages over those in common use, entirely originating from the reduction of the fire-box end, and which cannot be acquired in any other way.

With this object in View the invention consists in the peculiar construction hereinafter more particularly described and then defl- -nitely claimed at the end hereof.

In the accompanying drawings, Figure 1 is aside elevation of atube, showing one form of my invention. Fig. 2 is a similar View showing another form.

Referring now to the details of the drawings by letters and more particularly to Fig. 1, a represents portions of the tube of the original size of the same, and b a series of corrugations of any desired form or size made there in. At one end (the fire-box end of a boilertube) it is reduced, as shown at c, to a diameter preferably very slightly smaller than the narrowest part of the inside diameter of the corrugated portion. By this construction no cinder or other matter can enter the orifice or mouth of the tube that will not readily pass through the corrugated part, and thus the probability of the tube being choked or stopped up from the size of the particles admitted at the plain end will be completely avoided or reduced to a minimum.

Under certain conditions I may make one end of the tube larger than the original size, as shown at e in Fig. 2. This will be found advantageous in steam-boilers, inasmuch as it will contribute to keep the tubes clean by providing a more open and free discharge for such matter as may enter the tubes.

I do not limit myself to the exact forms shown, as the proportions of the various parts and the corrugations may be modified and one part may be used without another without departing from the spirit of my invention.

I am aware that it is not new to make a plain tube with a reduced end, as such atube is shown in the United States Patent No. 558,952; but the said tube was intended to be used with a ferrule on the reduced end, so that the tube-sheet was perforated with holes substantially of the size of the largest part of the tube, and therefore the advantages above set forth were not attained by the tube shown its furnace end reduced and its other end enin the aforesaid patent. larged, substantially as described.

What I claim as new'is In testimony whereof I affix my signature, 1. In a boiler a series of fire-tubes having in the presence of two witnesses, this 28th 5 their furnace ends of smaller diameter than day of August, 1899.

the body thereof in combination with a fur-U naee-tube sheet provided with perforations i i CHARLES WHITNEY fitting the reduced end of the tubes, substan- .lVitnesses: tially as and for the purpose specified. 'B. E. LINBROAM,

1o 2. Acorrugated malleable fire-tube having SHERMAN 7. FORD. 

